Floating roof drain



Get. 3, 1944. H. HAMMEREN FLOATING ROOF DRAIN Original Filed March 3l, 1942 Patented Oct. 3, 1944 FLOATING ROOF DRAIN hans Hammcren, Bethlehem, Pa., assigner to Bethlehem Steel Company, a corporation of Pennsylvania Original application March 31, 1942, Serial No.

Divided and this application December 17, 1942, Serial N0. 469,305

2 Claims.

This invention relates to a storage tank roof drain, and more particularly to a drain of the folding joint type for draining a iioating roof in a liquid storage tank, the present application being a division of my co-pending application, Serial No, 437,011, filed March 31, 1942.

Tanks which are used for the storage of highly volatile and inflammable contents such as oil or gasoline and which are filled and emptied a number of times a year, or tanks where fire protection is of prime importance, are customarily provided with floating roofs or decks for reducing the risk of re and the loss by evaporation as much as possible.

To retain their stability and buoyancy, especially in climates where there is a heavy annual rainfall, it is obviously necessary that such roofs be able to be well and quickly drained, and that the draining means do not introduce excessive side-pull which might set up damaging friction between the roof and the sides of the tank.

The principal object of this invention, therefore, is to provide a roof drain of the folding joint type so designed and constructed that the Weight of the drain will not exert excessive side thrust on the roof toward the side wall of the tank, but other objects, advantages and purposes of the invention will also appear hereinafter.

In order to make the same more clear, I shall now refer to the annexed sheet of drawings forming a part of this specification and in which like characters of reference indicate like parts:

Figure l is a vertical section of a complete tank, showing the floating roof and drainage pipe assembly diagrammatically;

Fig. 2 is a top plan view of the drainage pipe assembly straightened out to show its construction;

Fig. 3 is a side view, partly in section, of the swing joints connecting the several segments of the drainage pipe assembly; and

Fig. 4 is a section taken on the line 4-4 of Fig. 3, and showing the swing joint from the front.

Referring now to the various characters of reference on the drawing, a floating roof I of any desired type with central drainage is shown in Fig. l, in full lines in lowered position in the tank 2, and in dotted lines in various raised positions. Conventional side guides and sealing means are not shown, but may obviously be of any of the many designs familiar in the art. The same is true of roof supports, which for clearness are omitted from the drawing, but are the simple standard props, of angle iron or the like, which when the tank 2 is low or emptied of contents will support the roof about five feet above the tank bottom 3.

The construction consists of three swingable pipes-an upper short piece 4, a middle long piece 5, and a lower yshort piece 6. Swing couplings 'I, as shown in detail in Figs. 3 and 4, each braced by a welded bracket 8 of rolled sections, connect the separate sections of pipe together, as shown in Fig. 2, which also illustrates a modified swing joint 9 by which the whole system is attached at the top to check valve Ill and sump II in the center of roof I.

When the roof is at lowest point I2, i, e., about ve feet above the bottom 3, in Fig. 1, the middle long piece of pipe 5 is supported on a horse or similar fulcrum support I3 about three feet above said bottom, and is in balance about this support. The pipe assembly can therefore be swung into 'position I4, as the amount of fluid in the tank increases, without any side pull on the roof. After the assembly has passed said position I4, and reached positions I5 and I6, the angle between the two upper pieces of pipe is so large that the side pull will not be excessive. A smaller open distance between roof and bottom, say three feet, would call for the use of a number of short pipes.

Although I have thus shown and described my invention in considerable detail, I do not wish to be limited to the exact construction so shown and described, but may use such substitutions, modications or equivalents thereof, as are embraced within the scope and spirit of my invention, or as are pointed out in the appended claims.

Having thus described my invention, what I claim as new and useful and desire to secure by Letters Patent is:

l. The combination with a liquid storage tank, of a oating roof, a sump on said roof, a support on the bottom of the tank, and a drain of the folding-joint type suspended from said sump discharging outside the tank, said drain comprising a short upper pipe, a longer center pipe, and a short lower pipe, which pipes are connected together by swing-joints, the center` pipe being balancingly supported on the support when the roof is in its lowest position to substantially elim-A 

